This unit can fire both types of missiles. Tactical missiles are built and launched automatically, but strategic (long range nuclear) missiles must be constructed before launching. In Forged Alliance, strategic missiles can be built while the sub is moving, so it is wise if your economy can handle it to begin building these missiles right away. Because of the long build time, it is now unwise to assist a strategic missile sub in building its strategic missiles. Think of the sub as a mobile strategic missile silo, much less vulnerable to gunships and bombers, and a lot less likely to be discovered if hidden.

Strategic Missile Submarines have a high amount of health, can withstand quite a beating against an enemy navy when submerged, and can hammer a sea or land force from a very safe range. However it is not recommended to allow them to take on an opposing navy on their own in the open water, as their top speed and acceleration is the slowest of all naval units, and that will quickly bring the Strategic Missile Sub within counter-sub weapon range. As with all submarines, if you need to improve its speed simply surface the vessel to gain a speed advantage, although this makes it more vulnerable to surface fire.

Strategic Missile Submarines do not need to surface to fire their Tactical or Strategic missiles. Tactical missile defense units can stop its tactical missiles, but they have no effect on its strategic missiles. Conversely, strategic missile defense units can stop its strategic missiles, but they have no effect on its tactical missiles. A Strategic Missile Subs nuclear payload has a slightly lower inner damage than a traditional nuclear silo, however this will only matter to surviving experimentals. The cost per second in energy is slightly smaller than a traditional Strategic Launcher, but the build time is two minutes higher.